Arc Behavior in Rotary-arc Type of Load-break Switch and its Current-interrupting Capability for Different Environmentally Benign Gases and Electrode Materials

Abstract

MemberIn the purpose to find an alternative gas to SF 6 , this paper describes the results of current-interruption experiment for a rotary-arc type of load-break switch filled with CO 2 , H 2 , He and SF 6 at an absolute pressure of 0.1 MPa in case of ring electrode made of stainless steel. In addition, in case of the switch filled with CO 2 , current-interruption experiments were also performed for the ring electrode made of copper. The interrupting capability was found to be higher in order of SF 6 , H 2 , CO 2 and He. Moreover, the switch proved to have the higher current-interrupting capability for the copper than for the stainless steel. The phenomenon was found to arise from change in magnetic flux in an inner space of a ring electrode, depending the electrode material. This change in the magnetic flux also proved to result from variation of a resistance of the ring electrode.

Particle Composition of CO2-CF3I Mixture at Temperatures of 300-30,000 K

“…( iii ) CF 3 I concentration in a range from 0.9 to 1: As found in Fig. 5(c), a further increase in X CF3I from 0.9 to 0.99 results in marked diminution in the number density of CO 2 and COF 2 A further increase in X CF3I to 1 leads CO and C 3 O 2 to be absent, but resulting in production of C 5 . These phenomena lead the particles C 2 F 6 , I 2 , CF 4 and C 5 to be present as the principal particles, as already found in Fig.…”

“…At a temperature of about 2,000 K, CO 2 , COF 2 , CO and I shows higher number densities than other species. A further diminution to temperatures of 300-500 K results in decline in the number densities of COF 2 and I, but leads CO 2 , CF 4 , CO and I 2 to be present at high number densities of 10 24 m −3 order or above.…”

“…As mentioned in the previous section, CO 2 -CF 3 I mixture continues to consist of CO 2 and CF 3 I molecules, if being present around the room temperature inside the metal enclosure, because no energy to dissociate these molecules is given. However, the calculation conditions in the present research corresponds to the following: once after CO 2 and CF 3 I molecules decompose to atoms and further ionize to monatomic ions due to a sufficient high temperature, the temperature of CO 2 -CF 3 I mixture decreases to the temperature T .…”

Effect of magnetic field strength and admixture gas on current interrupting capability of a CO2 rotary‐arc load‐break switch

“…In addition, we have shown both theoretically and experimentally that the resistance of the ring electrode affects the characteristics of the applied magnetic field [3].…”

“…We have already examined factor (1) and have found that a copper ring electrode gives better performance than stainless steel [3]. In addition, we have shown both theoretically and experimentally that the resistance of the ring electrode affects the characteristics of the applied magnetic field [3].…”